Now every morning we awake to birdsong. All the singers are male, right? Well … not really.
When I took a class on birdsong years ago I learned that female birds don’t sing. This information came from centuries of bird observations made in Europe and North America. Charles Darwin even used it to describe how song evolved in male birds to attract mates and compete for territory.
Superb lyrebirds (Menura novaehollandiae) are the size of pheasants and native to southeastern Australia. The males are famous for their courtship displays which include shaking their elaborate tails and accurately mimicking a wide variety of sounds.
In the wild, superb lyrebirds mimic natural sounds. In 2009 there was a lot of construction at Adelaide Zoo. When the breeding season came Chook faithfully reproduced the sounds of hammers, power drills and workmen whistling on the job.
Close your eyes at the 3:15 mark and listen to the handsaw!
Every year my husband and I spend a relaxing two weeks at Acadia National Park where we enjoy spectacular scenery, wildlife, and hiking trails. Now that we’re heading home I’ll share some of the highlights. The best is a sound that I will certainly miss in Pittsburgh — the haunting call of the loon (Gavia immer).
In September common loons migrate through Canada and Maine from interior lakes to the sea. Each one migrates alone, independent of its mate and offspring.
One particular loon, distinctive because he was molting into winter plumage, often spent his evenings at the harbor. Every morning I heard him make the tremolo call at dawn (click here to hear) but last Wednesday, when the fog came up just after rain, he made a haunting wail call that echoed among the mountains.
Watch the video above to learn what the wail means.
October is sparrow time in Pennsylvania. Migrating warblers have left. Migrating sparrows have arrived.
Though swamp sparrows aren’t singing right now, the species is famous for their regional dialects. Over the winter they’ll be exposed to other sparrows with other dialects. Will they change their accents to match their winter friends or retain their dialects to use next spring?
The call is a warning. Goldfinches use it near the nest when there’s a dangerous predator nearby. Last Saturday I heard it repeated loudly for an hour while an immature Coopers hawk perched in my neighbor’s spruce tree. As soon as the hawk left the goldfinches stopped saying it.
Listen for the call and you’ll learn two things:
There’s a goldfinch nest nearby and …
There’s also a hawk, cat or other danger in the vicinity.
Brown-headed cowbirds are courting now because their victims are about to nest. The males sing a bubbly whistling song to attract a favored female. After she’s chosen a mate, Mrs. Cowbird lays her eggs in the nests of smaller birds whose own eggs and nestlings die while the foster cowbird chick thrives.
In cowbird society nest building and incubation never occur so the pair bond is cemented by courtship songs and postures. Amazingly, the quality of the male’s song really matters. That’s how the female decides who to accept and who to ignore.
What happens if a female can’t tell the difference between good and bad songs? What happens when one lady in the flock doesn’t follow the rules? Last year scientists learned that one tone-deaf female can upset cowbird society.
Researchers at the University of Pennsylvania led by Sarah Maguire inactivated the song-control centers of some female cowbirds’ brains so they could no longer distinguish between high and low quality songs. When placed in a mixed-sex flock these ladies reacted to all songs and did not stay with a chosen male for long.
Since male dominance among cowbirds is based on song quality the best guys usually get the best gals. However, when a tone-deaf female appeared in the flock she listened to all males equally and the minor males got a boost. The dominant males courted the altered female more vigorously. The other ladies were left in the cold.
Which guy will she choose? One tone-deaf female can mess up an entire social structure.
This morning I heard the sound of a lonesome dove.
When seeking a mate male mourning doves call like the ones in this video. Those who’ve found true love don’t need to sing because the cooing is a solicitation call, not a territorial defense.
Unmated males perch-coo from the heights as loudly as they can, “Ladies, I’m available.” It’s amazingly loud considering they don’t even open their mouths. A few have already begun calling in my neighborhood but the peak time will be late April through June.
Males also use flap-glide flight to attract female attention. Taking off with exaggerated wing-claps, they fly up above the trees and rooftops, then spiral down with stiff wings held slightly below their bodies. From a distance their silhouettes resemble kestrels or sharp-shinned hawks. They’ve fooled me more than once. Here’s my attempt at what they look like, gliding from left to right:
Today sunrise is at 6:49am so a lot of us are awake before the perch-cooing begins, but lonesome doves can be annoying in June when they start calling at 5:00am.
Quiz! Test your “birding by ear” skills with this video. In addition to the mourning dove there are at least seven other species singing in the background. Who are they?
(video by Carl Gerhardt, musicofnature.org via YouTube. Silhouette drawing by Kate St. John)